The pathways of dissimilation of arginine, proline, ornithine, citrulline and fructose in Pseudomonas putida will be determined, and the regulation of enzyme synthesis investigated. Blocked mutants will be isolated and the genes mapped, to determine if they are located in one of two demonstrated superoperonic clusters of genes which encode enzymes of catabolism. The pathway, regulation and genetics of histidine catabolism in Streptomyces coelicolor will be investigated.